This invention relates to a flexible elongated neck and more particularly to an articulating elongated inspection neck effective to shield radio frequency interference.
Invasive medical devices such as catheters, gastroscopes, colonscopes, endoscopes, and the like are commonplace in the diagnosis and the treatment of a variety of patient ailments. A medical professional inserts typically such devices into a patient and manipulates them to gather information about the patient""s condition for review and analysis.
These medical devices usually include an elongated flexible neck incorporating a sensor or transducer at one end and positioning apparatus at the other end. The flexible neck facilitates insertion and remote manipulation via the positioning apparatus.
The sensor gathers relevant information on a patient under examination. Such information can include relatively simple information such as temperature. The information can include complex information such as imaging information. In these more complex situations electrical signals are transmitted via one or more signal wires, cables or fiber optics inside the elongated flexible neck. Signals transmitted during ultrasound imaging are an example of electrical signals transmitted inside the elongated flexible neck.
The operation environment of invasive medical devices is rich with troublesome radio frequency interference (RFI) and electromagnetic interference (EMI). For example, hospital intensive care units have patient monitoring electronics that tend to emit RFI. Also, the inductive nature of ventilators and other motor-based appliances also generate electronic noise. And in operating rooms, certain electro-surgical devices, such as self-cauterization apparatus, generates broadband electric noise.
The electrical signals transmitted in the elongated flexible neck are weak and of minimal amplitude. Consequently, the presence RFI and EMI can inhibit or confuse the signals of interest. Diagnosis and treatment are hindered.
Even medical devices using such reliable elongated articulating necks as disclosed in U.S. Pat. 5,749,828 do not shield against RFI. The patent discloses a bendable neck constructed using pivotally joined tubular sleeves. But the linkage does not guarantee electrical communication between the sleeves. Consequently, electrical continuity along the neck critical for RFI shielding can not be guaranteed.
The fact that there is no guaranteed electrical continuity between the tubular sleeves disclosed in U.S. Pat. No. 5,749,828 is the result of the inability of manufacturing techniques. These techniques can not fashion surfaces that keep electrical communication between the tubular sleeves during bending of the neck. Even with high precision machining techniques, the edge surfaces of the tubular sleeves can not guarantee electrical communication throughout bending of an articulating neck.
There are two general approaches used to minimize and eliminate RFI and EMI. And they both have shortcomings. The first approach is to filter noise or interference out of the desired signals transmitted in the elongated flexible neck. But this approach is expensive and complex. The second approach involves the use of shielded signal cables. But adding braid or shielding to a signal carrying cables can affect its flexibility and adds to the girth or diameter of to the cable. And both are important. Maximum flexibility is need for inspection. Furthermore, the constant bending may cause fatigue and wear of the braidxe2x80x94This can result in the loss of electrical continuity, resulting in loss of the shielding effect. The invasive nature of some inspections requires a minimum cross-section or girth.
So there is a need for an improved elongated bendable neck providing RFI shielding.
An object of the invention is an elongated flexible neck providing RFI shielding.
Another object of the invention is a flexible elongated neck construction giving improved flexure properties.
Yet another object of the invention is an improved elongated articulating neck that provides electrical continuity along the entire length of the neck.
In a broad sense, the above and other objects are attained by an elongated flexible neck with a series of individual electrically conducting parts that incorporate the use of self adjusting electrically conducting members. Such parts each have a passageway there through and are pivotally joined together with the passageways being aligned along the length of the neck. A self-adjusting electrically conducting member connects immediately adjacent individual parts in electric communication. And the self-adjusting members maintain electrical communication between the parts throughout movement of the parts during flexure. So the neck maintains electrical continuity along its length. The spacing between the pivotally joined parts is sized to be a barrier to predetermined radio frequencies.
In another sense, the objects are attained by an elongated articulating neck including a series of individual tubular parts that provides radio frequency shielding by keeping the individual tubular parts in electrical communicationxe2x80x94thereby provide electrical continuity along the length of the neck. The tubular parts, which are capable of conducting electricity, have their openings aligned along the length of the elongated articulating neck to form a passage there through. A swivel tab is formed at one end the wall of the tubular parts; a counterpart swivel socket is formed at other end. Adjacent tubular parts are pivotally joined together by inter-engagement of the swivel tabs in the swivel sockets with the each swivel tab pivoting around a pivot axis. The swivel tabs have a recess formed therein with its opening positioned at the forward portion thereof. The edge surface defining the recess including a rear portion facing the opening of the recess along which is located the pivot axis of the swivel tabs. A biasing member extends from the wall into the swivel sockets. And such member terminates in engagement with the edge surface at the pivot axis of the swivel tab. The biasing member exerts sufficient force against such edge surface to maintain electrical contact therewith throughout flexure of the elongated neck. The spacing between the pivotally joined parts being sized to be a barrier to predetermined radio frequencies.
Another aspect of the invention provides an elongated articulating inspection neck having various bending radii. Such a neck includes a series of individual parts having an opening there though. The opening of the parts are aligned along the length of the articulating neck to form a passageway through the neck. Such parts are formed with a pair of opposed swivel tabs at one side and are formed with a pair of diametrically of counterparts swivel sockets at the opposite side. Accordingly, along the length of the neck the adjacent parts are pivotally joined together by inter-engagement of the swivel tabs in the swivel sockets. The wall of such parts is formed with a pair of diametrically opposed finger tabs located between the pair of swivel tabs that are on one side and with a pair of counterpart finger sockets located between the pair of swivel sockets at the opposite side. Finger tabs are moved into finger sockets during bending of the neck and are stopped by the bottom thereof to limit bending radius of the neck. And the finger tabs and the finger sockets are dimensioned to provide different a bending radius on opposite sides of the neck. And in some certain instances dimensions of the finger tabs and finger sockets vary along the length of the neck.
Advantages from the use of the instant invention are important. First, electrical continuity along the length of the flexible neck provides is an RFI shield that contains radio frequency emissions present within the neck and shields radio frequency emissions outside the neck from entering the interior of the neck. And the invention allows both engineering of bending radii and the amount of articulation of flexure.
Other objects and advantages will become more apparent as the invention is described in more detail with reference made to the as accompanying drawings.